GreenLawns provides a lawn fertilizing and weed control service. The company is adding a special aeration treatment as a low-cost extra service option, which it hopes will help attract new customers. Management is planning to promote this new service in two media: radio and direct-mail advertising. A media budget of $4,000 is available for this promotional campaign. Based on past experience in promoting its other services, GreenLawns has obtained the following estimate of the relationship between sales and

the amount spent on promotion in these two media:

S = -2R² 12M² 9RM + 20R + 37M,

Where

S = total sales in thousands of dollars

R = thousands of dollars spent on radio advertising

M = thousands of dollars spent on direct-mail advertising

GreenLawns would like to develop a promotional strategy that will lead to maximum sales subject to the restriction provided by the media budget.

(a)	What is the value of sales if $2,000 is spent on radio advertising and $2,000 is spent on direct-mail advertising? Enter amounts in dollars, i. e. $12 thousands should be written as $12,000